Dental impression device



March 4, 1952 w. T. SHEA 2,588,169

DENTAL IMPRESSION DEVICE Filed April 7, 1950 M74500? 7.' Shea Patented Mar. 4, 1952 William T. shes, Bufialo, N. Y.

Application April 7, 1950, Serial No. 154,506

7 Claims. (01. 32-19) This invention relates to apparatus for use in the science of dentistry and particularly in the practice of prosthetics.

In preparing dentures and particularly in the preparation-of more or less complete dentures, 'the'practice isto make an impression-of the interior-of the patient's 'mouth, particularly of the alveolar ridge, or of both alveolar ridges in the cases where both upper and lower dentures are to be made and fitted. From these impressions models are made for use by the prosthodontist or manufacturing dentist. These models are replicas of the upper and lower alveolar ridges of the patient after all contemplated tooth extractions have been made.

From these models the prosthodontist or manufacturing dentist makes what is known as a base plate tray, and upon this base plate tray he builds up a U-sh-aped wall of wax or the like known as a bite block and proportioned to approximately define the outlines of the teeth to be built up on the ultimate plate or denture. This wax bite block is not a representation of the individual teeth, but merely a solid wall defining the space which the teeth will occupy. The bite block por-- tion may be of wax or may comprise a'shellac base with a wax bite portion.

These bite blocks are then inserted in the mouth of the patient to determine the required depth of the teeth to be built up on the projected l denture and to determine the correct vertical alignment or registry of upper and lower plates,

the latter characteristic being known in this art as the determ nation of correct centric.

When proper adjustments have been made and. the patient finally bites down and both bite blocks are in correct relative position and the correct depth of bite has been determined, the dentist seals the sides'of the upper and lower biteblocks to each other by applying a hotspatulato the wax at one or more points along the line where the bite blocks meet. The bite blocks "are then'removed from the patients mouth,- and tongue-of the patient is pushed backward in the oral cavity and held in such position. The actualaccomplishment of this result in this man- -ner has heretofore been considered impractical because the interior of the patients mouth-is inaccessible when-the bite blocks are closedor brought together, and the degree of movement of any individual patients tongue to secure immobilization varies widely.

The present invention provides a simple device which may be incorporated in one ofthe bite blocks, more conveniently the lo er'bite block, at the time the bite blocks are made, for'use by the dentist in readily push ng back the tongue to just the proper degree and holding it so pushed back when the bite blocks are closed and ultimately sealed to each other. While a single form of the device of the present invent on s illustrated in t e drawing and described in the following specification, it is to be understood that that/form is by way of example only, and that many mechanical modifications ma be made without de art ng from the sp rit of the inventi n. which is limited only as defined in the appended claims.

In the drawing: Fig. 1 is a schematic representation of a --por tion 'of a h man head, particularly the mouth portion and the alveolar ridges, showing a pair of bite blocks in position and one form of the device of the present invention associated therewith; r

Fig. 2 is a ton planview of the lower bite block of Fig. 1; and

Fig. 3 s a fra mentary cross-sectional view on the line 33 of Fig. 2.

In'the several figures'of the drawing, like characters of reference denote like parts, and the numerals I0 and I I designate schematically the upper and lower alveolar ridges of a patient. Upper and lower b ase plate trays are designated I2, and l3, and the bite blocks carried thereby are designated 14 and 15, respectively.

The device of the present invention, in the form illustrated in "the drawing, comprises a generally cylindrical sleeve-like holder designated generally [6 and comprising an externally flattened portion l8 at one end and a tapered split threaded portion l9 at the other end. The flattened portion 18 is adapted to be embedded in lower bite block H3 at its front central portion when the latter is cast or molded, the sleeve l6 extending longitudinally with its split threaded portion outwardly of the front surface of bite block IS. The flats of portion I8 prevent inadvertent rotation of sleeve IS in the bite block.

A rod element 2| is preferably provided with a head formation 22 at its outer end and is threaded at its inner end as at 23 to screw into a hub portion 24 of an arcuate pushing plate 25.

After sleeve I6 is cast in position in bite block l5, rod 2| is inserted in sleeve l6 and the arcuate pushing plate 25 is threaded onto the inner end 23 of rod 2|. A knurled thumb nut 21 may be employed in conjunction with the split threaded portion IQ of sleeve l6, either to lock the rod 2| in a desired position of adjustment or. to cause just enough friction between rod 2| and the interior of sleeve l6, so that rod 2| will remain frictionally in any desired position of axial adjustment but may be manipulated axially in sleeve l6 when desired.

In using the device of the present invention, after it has been fully assembled with the bite block as described above, the dentist may either apply pressure to head 22 of rod 2| to hold the patients tongue in the approximate position indicated at 30 in Fig. 1, or he may push the tongue to such position by pressure upon head 22 and then look the pusher with respect to sleeve l6 by tightening nut 21. In either case the tongue is held back to whatever degree is necessary to immobilize the lower jaw of the patient, particularly with respect to lateral distortion, so that correct registration of the upper and lower jaws is assured, and, accordingly, correct centric of the bite blocks is readily attained.

What is claimed is:

1. Means for use in dental bite blocks comprising a sleeve adapted to be anchored in the front central portion of a bite block with its axis generally horizontal and perpendicular to the front surface of the bite block, a rod slidable in said sleeve and having a manipulating portion adapted to extend outside of the bite block and a generally vertical tongue pushing plate at the end of said rod adapted to be positioned interiorly of the bite block, and means for yieldably retaining the rod in axially adjusted position in said sleeve.

2. Means for use in dental bite blocks comprising a sleeve adapted to be anchored in the front central portion of a bite block with its axis generally horizontal and perpendicular to the front surface of the bite block, a rod slidable in said sleeve and having a manipulating portion adapted to extend outside of the bite block and a generally vertical tongue pushing plate at the end of said rod adapted to be positioned interiorly of the bite block, and adjustable means on said sleeve for causing the rod to be frictionally retained in axially adjusted position in said sleeve.

3. Means for usein dental bite blocks compris no ing a sleeve adapted to be anchored in the front central portion of a bite block with its axis generally horizontal and perpendicular to the front surface of the bite block. a rod slidable in said sleeve and having a manipulating portion adapted to extend outside of the bite block and a generally vertical tongue pushing plate at the end of said rod adapted to be positioned interiorly of the bite block, and means for selectively retaining the rod in axially adjusted position in said sleeve.

4. Means for .use in .dental bite blocks comprising a sleeve having a non-circular exterior surface for anchoring the sleeve in the front central portion of a bite block with its opposite ends exposed at the front and rear surfaces of the bite block, a rod slidable in said sleeve when said sleeve is anchored in a bite block and having a manipulating portion adapted to extend outside of the bite block and a tongue pushing plate at the end of said rod adapted to be positioned interiorly of the bite block.

5. Means for use in dental bite blocks comprising a sleeve adapted to be anchored in the front central portion of a bite block with its axis generally horizontal and perpendicular to the front surface of the bite block, a rod slidable in said sleeve and having a head portion at the end adapted to be positioned outside of the bite block and a generally vertical tongue pushing plate at the end adapted to be positioned inside of the bite block, and means for retaining the rod in axially adjusted position in said sleeve.

6. Means for use in dental bite blocks comprising a sleeve adapted to be anchored in the front central portion of a bite block with the openings at its opposite ends exposed at the front and rear surfaces of the bite block, a rod slidable in said sleeve when said sleeve is anchored in a bite block and having a manipulating portion adapted to extend outside of the bite block and a tongue pushing plate at the end adapted to be positioned inside of the bite block.

7. Means for use in dental bite blocks comprising a sleeve adapted to be anchored in the front central portion of a bite block with its axis generally horizontal and perpendicular to the front surface of the bite block, a rod slidable in said sleeve when said sleeve is anchored in a bite block and having a manipulating portion adapted to project outside of the bite block and a generally vertical tongue pushing plate at the end adapted to be positioned inside of the bite block, the face of said plate which is directed toward the rear of the mouth being convex in at least one direction.

WILLIAM '1'. SHEA.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 104,874 Osborn June 28, 1870 2,459,273 Freedland Jan. 18, 1949 2,505,056 Messine Apr. 25, 1950 

